Door seals, and in particular door seals for attaching around a body door opening in an automotive vehicle, must perform many functions. Primarily this includes prevention of moisture, such as rain, sleet, ice, snow, and wash water, from leaking into the passenger compartment. The seal must also prevent noise such as road, engine, and wind noise from penetrating into the passenger compartment. Additionally, the seal determines the quality of the fit between a vehicle door and the vehicle body. A good fit affects door closing effort and seal appearance, important elements in customer perception of vehicle quality.
To accomplish these functions effectively, a seal must not only be designed to properly interact with the weld flange to which it is typically attached, and the adjacent door and body surfaces, but must also must be easily attached to the weld flange while being more difficult to remove. Low seal attachment effort is necessary to expedite vehicle assembly, while seal extraction effort must be higher to provide seal retention and to prevent seal disengagement during door usage.
In addition to meeting insertion and extraction effort requirements, a door opening seal must also be capable of fitting on the vehicle weld flange. Variable thickness weld flanges around a door opening may cause a seal to fit improperly, thus decreasing its moisture and noise deterrent functions. Additionally, some body side openings have very tight corners to which the seal must be attached, making it difficult to achieve a tight fit. An improper fit due to either of these conditions adversely affects insertion and extraction efforts, and seal quality. Previous weather strip seal designs had to trade off high insertion efforts, including effort to maintain accurate alignment, on thick weld flanges in order to have acceptable extraction efforts on thinner flanges, and required costly molded details to go around tight body side assembly corners in order to avoid puckering of the seal.